Plastic pipe compression fitting

31 Oct 2013
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United Kingdom
Hello all

In my house, all the radiators are connected through a 10mm plastic pipe which goes directly into the valves with a similar to compression fitting joint.

In usual copper pipe compression joint, a brass or copper olive is inserted and then it is bolted on the radiator valve.

In my case, there is a plastic pipe instead of copper and a black plastic ring type equivalent to an olive and a plastic push thing.

As you would see from the attached picture, I am replacing one of the radiators but I need to extend the pipe also with a 15mm plastic pipe.

The questions are:

1. How do I connect this 15mm plastic pipe with the radiator valve which is of iron or steel. Can I use brass olive and bolt it onto valve? Would it damage the plastic pipe due to compression?

2. I have tried asking around in BnQ and Screwfix but they don't know what are those plastic rings around my 10mm pipe. Does anyone know what are these and can I get them for 15mm size?



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Green ring is the compression grab ring, compressed by the screw cap and the black o-ring is the seal that fits into the other end of the fitting/valve. If that 10mm plastic pipe is to be connected to a 15mm plastic pipe, not sure by your explaination, then remove the o-ring and grab ring and screw cap and then just use a 15mm to 10mm straight reducer.

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